现在分词怎么和过去分词并列？

OG12上的一道语法题：

Scientists have recently discovered what could be the
largest and oldest living organism on Earth, a giant
fungus that is an interwoven filigree of mushrooms and
rootlike tentacles spawned by a single fertilized spore
some 10,000 years ago and extending for more than
30 acres in the soil of a Michigan forest.
(A) extending
(B) extends
(C) extended
(D) it extended
(E) is extending

答案是A.  OG上给的解释是现在分词extending和过去分词spawned的并列。

以前没有碰到过现在分词和过去分词的并列，那位同学能解释一下，谢谢！

be spawned by 作后置定语修饰 表10,000 years ago 被孵出

extending 分词短语也做后置定语 表主动 而且是现在还在的动作

他们共同修饰interwoven filigree 是平行结构

请指教

现分和过分确实是能并列的～

that is an interwoven filigree of mushrooms and
rootlike tentacles spawned by a single fertilized spore
some 10,000 years ago and extending for more than
30 acres in the soil of a Michigan forest。

and 之前是描述以前的状态 some 10000 yearsago 出现肯定是过去时。而and后面，强调的是从过去起到现在 甚至将来都要extending。 所以extending是必须得。